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By Phil Jackson

Today’s digital electronic components—surround receivers, disc players, cable and satellite boxes, flat panel displays, computers, and NAS drives/streaming devices—are among the most delicate electronic devices in the home.  They are much more vulnerable to voltage surges, spikes, and fluctuations than are fans, lights, pumps, or major appliances.  Such electrical anomalies can damage circuit boards, deteriorate component performance, and corrupt custom configuration settings.  They can also cause software lock-ups, preventing full operation of the devices.  Electronic components can also be damaged by heat build-up due to improper ventilation.

Ironically, digital electronic components themselves are surprisingly ‘noisy’ devices (electrically speaking).  They can inject ‘digital noise’ back into electrical supply circuits, degrading the quality of the power supplied to other electronic audio and video devices in the home, and potentially degrading their performance.

Fortunately, a number of different kinds of specialized devices are available to address all these problems.  They can protect your equipment, maximize system performance, and mitigate the potential for damage because of anomalies in the electrical power system itself.

Surge Protectors

Known technically as Transient Voltage Surge Suppressors (TVSSs), these simple devices protect electronic components not just from indirect lightning strikes, but also from utility company surges and spikes, as well as from voltage surges caused by failure of appliances, HVAC, refrigerator compressors, and other line voltage devices within the home.  Since utility companies are legally allowed significant leeway in the consistency and level of voltage delivered to the home, they too can be the source of surge problems.  Whatever the cause, even small power fluctuations over time can damage the components on the circuit boards inside audio or video or network hardware.

Surge protectors are designed to protect components against most of these events.  Because direct lightning strikes can deliver surges with catastrophic power, no products currently available can protect home automation equipment from a direct hit. Inexpensive surge protectors are typically designed to sacrifice themselves in order to protect everything connected to them and must be replaced in the event of a significant voltage surge.

More sophisticated surge protectors use large relays, inductor coils, and/or special circuits to protect equipment without being destroyed themselves.  These protection devices typically also monitor the line voltage level, and will shut things down if the voltage exceeds (or falls below) a predetermined value, thus protecting the attached electronic equipment from the kind of repeated stresses that will shorten their lives.  In addition, most of these devices will reset themselves automatically once the voltage anomaly has passed.  Some even permit remote monitoring and remote re-setting of the device via the internet.

Line Conditioners

Even when working normally, electrical equipment in your home–or a neighbor’s–can generate “noise” in the electrical supply lines which can fill your video display with static lines or soft images, or make your audio system sound distorted, compressed or lifeless. This is especially true for equipment containing motors or switching power supplies.  A well-known example from the past is the visual static seen on a TV screen when someone uses a vacuum cleaner nearby.  Even the noise generated by digital components themselves can feed back into your electrical supply lines, and degrade the performance of audio and video components which are not protected by a line conditioner.

When line conditioners filter out this noise, they lower the overall noise level in your system, so you can enjoy the best performance your gear is capable of providing.  With today’s high resolution sources—High Definition (and Ultra High Definition) video, and high resolution audio sources like FLAC files and CD’s—noise reduction is critically important.  A number of different line conditioner types are available to fit your specific needs.  Discuss them with your system designer to find the most appropriate line conditioner for your system and budget.

Backup Power

The uninterruptable power supply (UPS) was developed to provide automatic temporary power for computers, in the event of a sudden power failure.  The UPS allows the computer user to follow the proper shutdown protocol, thus avoiding the loss of data during a power outage.   The UPS can also help solve other home automation problems.

11_Protecting_electrical_components_r2-02A common problem with electrical power today is the brief, fluttering power outage—where the lights dim or flicker without fully going dark.  When this occurs, the modern “switching-type” power supplies in electronic components can send unintended power pulses to the digital circuits in the system.  These circuits then misinterpret the pulses as requests to re-configure the set-up menu (for example).  Result: the custom configuration settings are lost or corrupted, and the user may experience sound with no picture, picture with no sound, or some other problem.

Incidentally, this problem seldom occurs with an outright power outage (when the power goes out without the preliminary flutter and flicker).  If a simple power outage occurs, many digital components will automatically revert to the configuration that was in use before the outage, once power is restored.

Another concern with power supply interruptions: as power finally is restored, the quality of the power your home receives during the first few minutes can be nasty, with significant spikes and fluctuations as well as temporary interruptions while the generators in the electrical delivery system stabilize and synchronize following the outage.  Some electronics manufacturers recommend that you turn your electronic gear off at the surge protector/line conditioner as soon as the outage is noted—or even unplug it—until power is restored, and other electrical devices like lights and fans in your home are running smoothly.  But performing this kind of system shut-down manually can be a challenge for the non-technically inclined user.  Instead, consider installing a UPS in your system, and let it be your sentry for these power fluctuations.

A further concern: if you own a back-up generator that comes online automatically when the utility power fails, be aware that it can produce nasty spikes as it ramps up to full power.  In this case, make sure your electronic components are protected with high-quality surge protector/line conditioners to buffer them from potentially damaging start-up transients.  Otherwise, high-quality digital components can easily be damaged by these on-site backup generators.

And now a word about whole-house surge protection/line conditioning strategies.  Some homes today have high-capacity devices designed to protect all of the electrical and electronic equipment inside the home from spikes or voltage surges that originate upstream, outside your home.  These sources can include your utility company’s electrical generation plant, lightning strikes which occur in the neighborhood, or electrical noise that your next-door neighbor’s electrical equipment dumps back onto the public utility lines.

While these systems do protect you from power anomalies that originate outside your home, whole-house devices won’t protect your sensitive electronic gear from potentially damaging electrical events that originate within your home: appliance failures, a TV with an intermittent power supply problem, or even the “normal” operation of motors and computers.  So it’s always smart to protect electronic gear (including DSL/Cable modems, routers and set-top boxes, plus Satellite receivers) with dedicated surge protectors/line conditioners, even when a whole-house system is in place.

Remote Power Monitoring and Control

Some of the latest surge protectors, line conditioners, and UPS devices—the BlueBOLT line by Panamax/Furman, for example—are internet-enabled.  This allows them to be remotely monitored and controlled.  Some of these models can detect power failures, power interruptions, brownouts, voltage spikes, and other voltage events, and report them via email to the owner and/or dealer who installed the equipment.  The dealer can then troubleshoot the problem online, and even remotely reset the equipment without rolling a service vehicle.

The user benefits from remote monitoring of these power conditioning devices are significant: immediate resolution of the power problem, reduced service costs, and not having to wait for a service appointment.  In addition, preventive network maintenance strategies—such as scheduled rebooting and automatic rebooting—make solving network-related problems quick and easy without user intervention, vastly improving system reliability.

Thermal Management

It’s a simple fact—heat kills electronics.  Most consumer-grade home electronics are designed to operate at no more than 110° Fahrenheit, and are most happy below 85 degrees.  Temperatures hotter than this can shorten the lives of components—either by cooking the semi-conductors or by shortening the lives of capacitors or resistors.  Without active thermal management, temperatures in typical residential installations (inside closed cabinets or closets) can easily exceed 110°F, which will eventually cause component damage.

A temperature-controlled fan system (with a suitable cool air intake, plus a warm air outlet far enough away from the intake so that it won’t short-circuit) will ensure that the electronic components stay much cooler than 110° Fahrenheit.  This will extend the life of the electronic devices.  A qualified system designer can design an active thermal management system to protect your electronic investment.  See Proactive Heat Management.


Today’s audio, video, and home networking equipment are delicate devices which need appropriate power management and protection as well as active thermal management in order to maintain consistent and reliable operation.  Devices to management power and to actively manage operating temperatures are available in a broad range of price points and features.  A qualified system designer can specify the right products to meet your needs and your budget.